Yellow Warbler
Chickadees, nuthatches and warblers foraging their way through forests have been shown to spur the growth of pine trees in the West by as much as one-third, according to a new University of Colorado at Boulder study. The study showed birds removed various species of beetles, caterpillars, ants and aphids from tree branches, increasing the vigor of the trees, said study author Kailen Mooney. Mooney, who conducted the study as part of his doctoral research in CU-Boulder’s ecology and evolutionary biology department, said it is the first study to demonstrate that birds can affect the growth of conifers.